hmm the fitness trackers i use show mountain biking as burning more calories

if you think about it the road bikes are going to be a lot more efficient then a mountain bike so even at 75% output it might take a road biker 20 minutes to do 5 miles but a mountain biker would take an hour

I used to burn more calories when I rode my roadbike, and that is because I would hammer 24MPH+ for 20 miles at a time before slowing down or resting… unless I was riding up in the hills, wherein my lowest gear ratio was a 39t x 23t, so lots of calories were burned there as well. Meanwhile, my current mountain bike (Surly 1x1 with lots of accessories + fat fat 24"x3" tires on 2.5" wide wheels + Alfine hub) weighs 48 pounds, so I am getting a pretty good amount of calories burned even on low-key rides.

QUOTE from MTBR.COM: You have given Brewtality too much Reputation in the last 24 hours, try again later.

If a road bike and a mountain bike were riding side by side on the road, the mountain bike having fatter tires, less air in the tires ,more weight, more area to catch wind, would be harder to ride and would never keep up, if both riders were equal, it seem pretty simple to figure, the road bike would use less energy and energy equals fuel that is calories.. what was so hard about that???
Then put the mountain bike on the trail and it has even more resistance with more turns per mile, mud, sand, gravel etc.
I think someone has been smoking left handed cigarettes, if they think a road bike burns more calories..LOL!!

I'd have to agree with you. Given the gearing, the MTB ride in your scenario should take longer. At 75% effort the only difference should be time spent riding.

Wow, only one guy got it right. If 75% effort is given (which it is), it doesn't matter what you're doing, or what you're doing it on. Time spent doing it is the only thing that effects calories burned. And because the road bike is more efficient, he'll cover the 5 miles in less time, and therefore burn less calories.

I asked myself the same question about 10 years ago and actually found that I burned more calories on the road bike. On a road bike you can push more of the time and it's easy to maintain a certain bpm or watts output, but on a mountain-bike there will always be technical sections or downhill sections where you can't give it your all. I do however believe that mtb is much better exercise all around, road racing only needs legs, lungs and heart.

If you want to be a supremely fast mtb:er it's good to get some road time in to build legs and cardiovascular.

If you want to be a supremely fast road racer it's good to get some mtb time in so that the odd slip and slide, curb or gravel won't put you on your behind.

Wow, only one guy got it right. If 75% effort is given (which it is), it doesn't matter what you're doing, or what you're doing it on. Time spent doing it is the only thing that effects calories burned. And because the road bike is more efficient, he'll cover the 5 miles in less time, and therefore burn less calories.

Exactly, though, Intervals (so explosive power bursts or short sustained efforts) are proven to have a higher residual caloric burn (the calories you burn after the exercise).
The mountain bike tends to be more bursts and recovery where the road is more sustained efforts.
If all was equal, the road and MTB you were to average 170 HR for 1 hour the caloric burns would be similar but the over all caloric burn would be higher if you tracked after effects.

There are so many variables, in the garmin forums the calorie question has always been heated. Some think that the unit over estimates, under estimates etc when nothing (even in a lab) is within 5% and that is with a full lab setting.

I have always agreed with calorie tracking to keep people aware BUT not as an absolute. If you are tracking caalories you are more aware of your intake and use than if you are not. If at the end of the day you are looking at 'I ate 2300 and burned 2400 I am good" you will never succeed as the accuracy of any count/measure is a general term.

I think it's complete conjecture and impossible to compare, which is why none of the calculators are ever accurate, with the exception of maybe some of those hub mounted calculators that know speed, cadence, etc, and calculate pretty well. It would depend largely on the trail and the road in comparison. If it's a smooth flat road being compared to a steep technical extended climb, the MTB would require more effort. If it's a flat, smooth singletrack ride against a tough steep road climb, the road bike would require more. It's just impossible to compare.

Mtb burn more

I do agree that time spent would be less on the road so you burn less calories. Also, when I climb on the road bike, even the steepest road I'd can still crank at 5-6mph. At that speed you body need less core work out because faster you can go the less you have to fight for balance.

On the Mtb, some climb I can only travel 3mph and that's taking every bit of my balance to stay on the line not to mention extra surge of power to get over ledge and water bar.

So even though 75% of max on both road and mtb, Mtb would burn a more due to the extra use of muscle to maintain balance.

It's hard to gauge but in general mtb is, by nature, more interval, and road is more steady. Even with some hills thrown in.
And in general over same time, road bike burns more. Over same distance, mtb wins.
Gotta better 1 for ya. Control the type and amount of food you eat because it only takes a few minutes to eat, as compares to hours of exercise to burn the same calories.
Go for a ride when you wake, before eating, or after a 45+ minute intense workout to tap into stores fat instead of food.

In the scenario, the mountain biker burns more calories. Road bikes are very efficient and pavement adds less rolling resistance than a fire road. So it just takes less time and less total energy for the roadie to finish the five miles.

As far as which one is a better aerobic exercise, I think it's a lot harder to sort out. The terrain on an off-road ride frequently obligates the rider to ride hard and just as frequently prevents the rider from doing much more than piloting the bike, which certainly also costs energy. On a road ride, even in fairly hilly terrain if the bike has low gearing, it's possible to cruise at very low effort. For the same reasons, though, it's a lot easier to do structured workouts on a road ride, including stuff like 15-30 minute intervals at maximum intensity for that time. So it's possible to use more effort too.

I think for purposes of weight loss, it's actually more useful to think about which kind of riding is more fun, or motivates a person to work harder. For example, I have a hard time riding hard on my mountain bike outside of racing unless I'm climbing. It's just demoralizing for me to dump a lot of power into my bike only to have to slow down for a sharp turn or lose a lot of speed over an obstacle. I'm a lot happier if I just flow at whatever speed feels natural to me in the terrain, or maybe push things just a little bit. I pedal pretty much continuously regardless, but if I'm not trying to do speed work, I'll choose an easier ratio.

On the road bike, even if I start with the intention of doing an easy ride, I tend to push my pace. If I get into rolling hills, I'll start trying to carry speed up a hill, charge the top, shift into a bigger ring and push the descent, etc. I really like that kind of terrain. Anyway, I think I work on my aerobic fitness more when I'm road riding, although it's certainly not as rounded a form of exercise as mountain biking - something some other posters have already mentioned.

A lot of people find road riding really boring, though. If a workout's no fun, it's a lot harder to keep doing it. Better to go with something that may be a little less effective but is more interesting, if it keeps you motivated and you actually do it.

Go for a ride when you wake, before eating, or after a 45+ minute intense workout to tap into stores fat instead of food.

Yep, thats exactly what I did to get totally RIPPED. Your body will use fat stores as the immediate energy source for the pre-breakfast ride. However, I did notice body fat makes for a poor source of high performance-related energy(more prone to bonking HARD) and rightfully so...since it is genetically a source of emergency fuel - intended for only the most basic of sedentary life functions(i.e; eating, sleeping breathing, etc.).

Oh, the MTB burns way more calories than the "efficient" road bike, according to my HRM.

Since I've been "training" for this cyclocross thing (first race is next Sunday), I've been very loosely following a cyclocross training regimen. They promote road cycling as both heavy endurance training and for "recovery rides", spinning at high cadence at around Zone 1 (this is the type of ride I will do today). However, as far as bike handling is concerned, MTB'ing is truly superior over road riding in regards to cyclocross training. I throw in MTB'ing in my routine or I ride trails AND road with my cyclocross bike (like what I did yesterday).

Yesterday I was descending a pretty rough fire road on my CX bike and, what I thought was a stick, was actually a rattlesnake. Last split second, I bunnyhopped it. If I was ONLY a road rider with no other background, I highly doubt I would've been able to do that, that quick. But, I ride BMX and MTB still and can rock a decent bunnyhop.

At the clinic I attended, we had a drill where we had to go down into a small wooded singletrack area, dismount, carry, and run up the hill as fast as we could. I was suprised how many people couldn't ride DOWN into the pit. Many people had to walk down it. Those who were MTB'ers rode down it.

FWIW, road riding is a great calorie burner, but even if MTB'ing doesn't theoretically burn more calories, it sure does offer incredible fringe benefits, especially for cyclocross riding.

It's obvious the mtb will take more effort under the prescribed circumstances (the flat 5 mile 75% effort thing on pavement vs dirt/gravel). It's like trying to compare which is more enjoyable, though of course I find mountain biking more enjoyable in general, but I know roadies who say just the opposite...suum quique

You can measure with a power meter and MEASURE actual energy expenditure in Watts, that way is dificult to lie to yourself like I did before, it is disheartening but some days you feel like you did a maximum effort (yes with recovery periods and all) and you discover a much lesser performance, the only thing is that this thing is expensive.

Used to train with a HR monitor. An hour trail ride at 75% max effort burned more calories for me than an hour road ride at 75% max effort. The higher HR/cal output was probably due to engaging more, different muscle groups. I could push 100% effort on a road bike in various conditions, (wind, rain, group pace lines, etc.) but still could not burn as much as what I did on a mediocre trail ride.

FWIW, the HR monitor was set up to my body type and body mass as per the instructions provided. There was no setting on it to distinguish different activities. It didn't know if I was cycling, running, or play badminton.

i was gonna say, 75%=75% but that's just legs right,or are you adding all the muscle groups up,if you just measure leg output then after a few hrs the other muscles used will burn more calories on the mtn bike,arms and core.

If a road bike and a mountain bike were riding side by side on the road, the mountain bike having fatter tires, less air in the tires ,more weight, more area to catch wind, would be harder to ride and would never keep up, if both riders were equal, it seem pretty simple to figure, the road bike would use less energy and energy equals fuel that is calories.. what was so hard about that???
Then put the mountain bike on the trail and it has even more resistance with more turns per mile, mud, sand, gravel etc.
I think someone has been smoking left handed cigarettes, if they think a road bike burns more calories..LOL!!

But if both riders are riding at 75% of capacity, the difficulty of their work is irrelevant. If I'm climbing a mounting using only my arms and using 75% of my maximum HR, and you (as an idnetically sized and shaped and fitness of an identical level) were juggling bananas with only your feet and using 75% of your maximum HR, then we're burning exactly the same number of calories. Granted, if we're talking about an equal distance, then it's likely that the MTB'er will take longer to cover that distance, so yes, he'll use more calories, but only because of the time factor.